金黄色葡萄球菌感染小鼠乳房炎模型的建立

Establishment of mastitis modle in mouse by artificial infection of Staphylococcus aureus

取25只分娩8～10d的昆明系小鼠随机分成5组(n=5),分别为阴性对照、生理盐水(pss)组和不同剂量金黄色葡萄球菌(1.0×102cfu/50μL、1.0×103cfu/50μL、5.0×103cfu/50μL)试验组,经乳头导管对第4对乳腺50μL/只注射,24h后观察结果,一侧乳腺甲醛固定制作切片观察组织病理变化,另一侧冰上研磨后取匀浆用高盐甘露醇鉴别培养基进行细菌计数,检测组织匀浆上清中的TNF-α含量。结果显示,试验组随着注射细菌数量的增加,病理变化加重,分离到的金黄色葡萄球菌数量显著增加,乳腺匀浆中TNF-α含量明显升高。结果表明,注射1.0×103cfu组可以引起较典型的小鼠乳房炎,且病理变化适中,适合用来建立金黄色葡萄球菌小鼠乳房炎模型。

25 Kunming mice 8-10 days postpartum were randomly divided into five groups：control group（A group）,physiologic saline group（B group）and three treated groups,1.0×102 cfu/50 μL（C group）,1.0×103 cfu/50 μL（D group）,5.0×103 cfu/50 μL（E group）.50 μL physiologic saline or Staphylococcus aureus liquid was injected into the forth mammary glands,respectively.All the mice were sacrificed 24 h after treatment.One side of the forth mammary glands was soaked into 10% formalin liquid,prepared for pathological section,another side was homogenated,centrifuge,collected supernatant for further analysis.One part of supernatant was inoculated on the high sodium chloride manicol medium to isolate and counte S.aureu.Another part was used to detect the concentration of TNF-α in the supernatant.The results show that three treated groups have a dose-response to pathological finding of mammary glands,the counts of S.aureus and the concentration of TNF-α.Group D（1.0×103 cfu/50 μL）was suitable for the replica of mastitis modle in mouse.